To diagnose certain gastrointestinal diseases, an apparatus may be used to collect tissue cells from the gastrointestinal tract for analysis outside of the body. Typically, such an apparatus may include a material that is absorptive or abrasive for collecting the tissue cells. The material may be attached to a retrieval string so that it may be retrieved from the gastrointestinal tract or it may be allowed to naturally pass through the digestive system. Sometimes the material is compressed and encased within a capsule that is swallowed and naturally dissolves within the gastrointestinal tract.
However, conventional methods of collecting cells from the gastrointestinal tract may suffer from several deficiencies, which reduce the accuracy and reliability of the diagnoses, as well as increase the discomfort to the patient. For example, a typical cell collection material may be designed to collect cells from a body lumen with a relatively uniform size. As such, typical cell collection apparatuses may be incapable of adequately collecting cells from a body lumen with portions of varying size. Additionally, the expansion properties of the cell collection material may be adversely affected by being compressed within a capsule for long periods of time. As a result, the material may not expand to a suitable size or shape once released from the capsule.
Accordingly, there may be a need for improved methods and devices to collect cells from the gastrointestinal tract of a patient that overcome some or all of the above deficiencies.